Illumination & Displays

Fans of LEDs say this bulb's time has come

L.E.D. bulbs, with their brighter light and longer life, have already replaced standard bulbs in many of the nation's traffic lights. Indeed, the red, green and yellow signals are -- aside from the tiny blinking red light on a DVD player, a cellphone or another electronic device -- probably the most familiar application of the technology. But they are showing up in more prominent spots.